 Increase in the total volume of the spherulites results in their interaction as well as shrinkage of the polymer, which becomes brittle and easily cracks under load along the boundaries between the spherulites.Alignment of the polymer molecules within the lamellae results in birefringence producing a variety of colored patterns when spherulites are viewed between crossed polarizers in an optical microscope.In particular, the so-called "Maltese cross" is often present which consists of four dark perpendicular cones diverging from the origin (see right picture), sometimes with a bright center (front picture).